Angular momentum of the solar system

Paradox of the angular momentum

The angular momentum is a physical quantity expressed in kilograms per square meter per-second (kg.m2.s-1). An example of application of this physical quantity is in the motion of planets around the Sun. The angular momentum of a system is equal to the sum of the moments of the system (rotational angular momentum, mainly from the Sun whose mass is large and angular momentum of revolution, mainly Jupiter and Saturn). In the solar system, the Sun has captured 99.86% of the total mass of dust and gas of the original nebula. Jupiter, the largest planet in the system, has captured 71% of the remainder. The other planets have shared the residue of the gravitational evolution. The angular momentum of rotation is approximately 1042 kg.m2.s-1 and the angular momentum of revolution is about 3x1043 kg.m2.s-1, i.e. 30 times. Then there is a paradox because the planets are only 1% of the total mass of the solar system should have only a small part of the angular momentum of the Sun, while it represents 97% of the total angular momentum. In interstellar clouds, there was proto stellar disks from which escapes a bipolar ejection of material.

What explains this transfer of angular momentum of the Sun to the planets? This ejected material is much more intense than that of the solar wind current. The origins of the solar system, Sun also produced, much more intense ejections of coronal mass ejections and it is these that would have transferred its angular momentum to the young objects in the cloud formation. The planets and the Sun formed at the same time, there is 4.5 billion years, from proto solar nebula. Is the isotopic dating, which confirms that date. Indeed the natural radioactive decay of uranium atoms, from either the Earth or the Moon, or meteorites, we give the half life was calculated at 4.5 x 109 years.

Image: Calculation of angular momentum in our solar system. The total angular momentum is equal to the angular momentum of rotation, mainly the sun and the angular momentum of revolution, mainly Jupiter and Saturn.

Composition of solar system objects

Go up the chronology of events. There are about 14 billion years, the Big Bang occurs. The solar system, from the isotopic dating was condensed, there is about 4.6 billion years. But beyond the dating methods, the operation of the solar system, we learn what could have happened to its origin, in particular, studies of the composition of solar system objects. The giant planets have a composition similar to that of the Sun, they are composed of hydrogen, deuterium and helium. The terrestrial planets have been enriched in refractory materials, comets will inform us about the ratio of deuterium to hydrogen (D / H). All these elements enable us to reconstruct a realistic scenario on the formation of the solar system. Big Bang and after the birth of stars, nucleosynthesis heavier elements, the explosion appeared in the final phase of the first stars. The stars have ejected elements that are dispersed in the giant clouds of material and there are 4.5 billion years, occurred near a spiral arm of the Galaxy, a compression of our solar nebula proto.

Condensations of matter appeared and then a gravitational collapse occurred in the center. The pressure and density would increase and the temperature became huge (about 10 million kelvin), generated by nuclear reactions in the center of the collapse. Meanwhile bipolar ejections occurred intense material. Local instabilities proto planetary disk collisions have materials and agglomeration, then gradually formed tiny planetoids made of refractory materials, near the Sun, silicates and metal oxide, a little further and ice of complex organic molecules even further (> 7 AU). 7 objects between AU and 30 AU have undergone intense gravitational perturbations caused by giant planets, causing huge collisions in the solar system. These cataclysmic bombardment intensity, occurred for about 600 million years. It was during this unstable phase of the system, the Moon has condensed the result of a collision between Earth and another planet (Gaia). All objects in the solar system, even small ones, have suffered the impacts of heavy bombing.